Yuuki's appearance also change in the next chapter, her hair got longer and she looks more mature she pushes kaname on to the bed and sucks his blood ( because kaname notices she was thristy and said don't hold back)

and :
Omg, forum Vampire Knight says that in vampire world incest ( marriage between brother and sister) is accepted and common because it is commonly used to keep the pure blood trait. Kaname and Yuuki's mom and dad are brothers and sisters, and they got married. Yuuki was also born to marry Kaname. they were engaged at birth.

= = = = = = = = = = = = = = = = = something else I have found.

Yuki is the daughter of the Kuran family.
Kaname said that Yuki was the child born to become his wife.
In the Pureblood race, incest isnt uncommon.

Yuki was placed on a bed inside and she started to crave blood.
She looked older, maybe it was because of her vampire genes had returned causing her hair to be longer.
Kaname told her not to hold it (the craving) in, and she pushed him down on the bed and started sucking his blood and crying at the same time.
Kaname hugged her and told her that He held on to an anxious emotion, waiting for this day. ( I dont know how to correctly translate this sentence. It made sense in chinese though)

Yuki remembered her parents and became confused. Kaname hugged her from behind and calmed her down.
Yuki said that it is abnormal for her to like Kaname, her own brother.
But Kaname replied, "So? We are bethrothed"
You find out that their parents are also brothers and sisters.

Rima who found out that Shiki isnt Shiki, ambushed Ichijou and Rido.
She fought with Rido and got hurt in her abdomen.
Ichijou tried to help her, but he was stopped.
Rima yelled for Shiki to fight for his own body.
Shiki heard her and started trying to regain control.

Yuki smelled the scent of Rima's blood, but was relaxed that it wasnt Zero's blood.
Then she felt depressed bc she remembered the expression Zero had when he found out about her pureblood statues.
She went to in front Zero's room.
Yagari came back.

now i'm confused....b4 this chapter i was so sure that yuki would choose zero but now i don't know anymore.....ahhhhhhhhhh i REALLY want her to pick zero!!!!! but if she were 2 end up with kaname i guess i can live with that......but if zero end up dieing at the end of the manga i'm going 2 b SOOOOOOOOOOOO mad!

god!!! what i was suspecting since chapter35 was release is finally revealed as the truth...i don't really know how to react but heck i can't wait until its released in english....i hope zero doesn't get hurt he deserves some happiness....

here's some more spoilers i posted the first anime pic in my thread :3

-yuuki after being awaked, suddenly her hair grow up (like they were in the past)
- a second after she wake up, she feels a "desire", and go on top of kaname, and start biting him. in that moment we see flash of a strange place, like a cave, and there's a strange symbol all covered in blood!

- now I start to understand why rido wants her......she has a power out of the normal! while she was crying and feeling hurt for her parents death all the wall of the room they were in started break up, just with her "crying"....I can't image what she could do if she acytually used a serious attack with her own will....
- aidou and kain comes to know about yuuki being a vampire and kaname's younger sister.
- kaname says that "yuuki has born for the purpose of becoming his bride"
- rima knows shiki is not shiki and asks even directly to him.
- Kaname tells yuuki that "her father and mother were brothers aswell" and so he says there's no problem in being his finac?e...
- while they're talking all of a sudden yuuki feels in the hair someone's blood...kaname tells her to stay in the room and that he'll come back soon but yuuki opens the window to see what is happening...it's shiki's body...rima is attacking him but she says he's the worst for using someone else body and make it hurt...but it seems rido regenerates himself contless times....when rima is attacked at surprise by rido, ichijo save her and tells rido to stop but rima says "your so stupid shiki, for making others control your body! you should take control of your own body" and then it seems like shiki is tring to take control back of it, rido infact is like blocked for an istant ...
- yuuki escapes from the place where she was (i suppose kaname's room) and find kain and aidou there. kaname asked them to not let yuuki go our of the room, but yuuki orders them to get out of the way because "there's a place I must go to" then she says "if you don't want to be scolded by kaname-senpai then accompany me where I'm going...first of all to the Day class dormitory"

I don't know if yuuki used some power, mentally or so, but aido after she glare at him keep his head like something has happened..or was it a "can't be helped" reaction? well I'll leave to you guys the interpretation XD

- the place she goes to seems to be zero's room...but the chapter ends with her in front of the room in the moment she's knocking the door and she thinks "Zero..." so i suppose she went to his room